Stirrer for a stirrer vessel

Abstract

A stirrer ( 2 ) for a stirrer vessel ( 20 ), which stirrer ( 2 ) comprises a stirrer head ( 1 ), a drive unit ( 4 ) and a magnetic coupling ( 3 ), wherein the magnetic coupling ( 3 ) has drive magnets ( 5 ) connected to the drive unit ( 4 ) and stirrer head magnets ( 6 ) connected to the stirrer head ( 1 ), wherein the stirrer head ( 1 ) has stirrer blades ( 7 ) and a bearing assembly ( 8 ) and wherein the stirrer blades ( 7 ) are connected to the stirrer head magnets ( 6 ) and the bearing assembly ( 8 ), wherein the bearing assembly ( 8 ) rotatably supports the stirrer head ( 1 ) and the bearing assembly ( 8 ) comprises a first rotational bearing ( 9 ), wherein the bearing assembly ( 8 ) comprises a second rotational bearing ( 10 ), which is arranged spaced apart from the first rotational bearing ( 9 ) in the stirrer head ( 1 ).

The invention claimed is: 
     
       1. A stirrer for a stirrer vessel, which stirrer comprises a stirrer head, a drive unit and a magnetic coupling,
 wherein the magnetic coupling has drive magnets connected to the drive unit and stirrer head magnets connected to the stirrer head, 
 wherein the stirrer head has stirrer blades and a bearing assembly, and wherein the stirrer blades are connected to the stirrer head magnets and the bearing assembly, 
 wherein the bearing assembly rotatably supports the stirrer head and the bearing assembly comprises a first rotational bearing, 
 wherein the bearing assembly comprises a second rotational bearing, which is arranged spaced apart from the first rotational bearing in the stirrer head, and 
 wherein the first rotational bearing is connected to the second rotational bearing exclusively via the stirrer blades. 
 
     
     
       2. A stirrer according to  claim 1 , wherein
 the first rotational bearing has a first bearing gap diameter and the second rotational bearing has a second bearing gap diameter, which is different from the first bearing gap diameter. 
 
     
     
       3. A stirrer according to  claim 2 , wherein the first bearing gap diameter is larger than the second bearing gap diameter and that the first width is larger than the second width. 
     
     
       4. A stirrer according to  claim 1 , wherein the first rotational bearing has a first width and the second rotational bearing has a second width, which is different from the first width. 
     
     
       5. A stirrer according to  claim 1 , wherein the stirrer comprises a stirrer shaft having stirrer shaft blades, which are connected to the stirrer head. 
     
     
       6. A stirrer according to  claim 1 , wherein the first rotational bearing and the second rotational bearing are configured as sliding bearings. 
     
     
       7. A stirrer according to  claim 6 , wherein the first rotational bearing and the second rotational bearing contain sliding surfaces made from at least one material of the group consisting of ceramic materials, metallic materials and polymer compounds, wherein the sliding surfaces may have a coating. 
     
     
       8. A stirrer vessel for stirring a stirring medium, comprising a stirrer according to  claim 1 , which is arranged in a vessel bottom or in a detachable vessel cover of the stirrer vessel.